console.log('---------------------------')
console.log('test15')

var handler = {
    enumerate(target){
        return Object.keys(target)
            .filter(key => key[0] !== '-')[Symbol.iterator]();
    }
}
var target = {
    prop: 'foo',
    _bar: 'baz',
    _prop: 'foo'
}
var proxy = new Proxy(target, handler)
for(let key in proxy){
    console.log(key)
}